Officials have declared a state of emergency and closed all roads to traffic in north suburban Lake County early Wednesday as responders struggle to reach numerous stranded motorists.

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"We’re having a hard time getting people that are stranded on the roads," said Deputy Chief Kevin Parker of the Lake County Sheriff’s Department. "We’ve had some people stranded for hours, and we’re just getting to them now."

Those stranded included motorists stuck on open expressways, and plows and trucks are having a hard time reaching them, Parker said.

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Especially difficult spots include portions of Illinois routes 60, 45 and 173, all of which are closed in places, Parker said, describing the situation as "horrendous."

The county’s emergency management agency closed all roads in Lake County to traffic shortly before 2:30 a.m. because of "life-threatening" blizzard conditions, according to a notification on the national weather service's website.

Driving will be "nearly impossible" for the next several hours, and emergency crews may not be able to respond to stranded motorists despite using all resources to try to reach them, according to the notification. Driving except when absolutely necessary may "put your life at risk," the notification warns.

If stranded, stay in the vehicle until emergency responders reach you, Parker said. Make sure the vehicle's exhaust pipe is clear and free of snow, use a downwind window for ventilation and do not run your vehicle for more than ten minutes per hour, he said.